Page BUICK LACROSSE 2008 Owner's Manual

Tires
Your new vehicle comes with high-quality tires
made by a leading tire manufacturer. If you ever
have questions about your tire warranty and where
to obtain service, see your vehicle Warranty
booklet for details.
{CAUTION:
Poorly maintained and improperly used
tires are dangerous.
Overloading your vehicle’s tires can
cause overheating as a result of too
much exing. You could have an
air-out and a serious accident. See
Loading Your Vehicle on page 4-21.
Underinated tires pose the same
danger as overloaded tires. The
resulting accident could cause serious
injury. Check all tires frequently to
maintain the recommended pressure.
Tire pressure should be checked when
your vehicle’s tires are cold. See
Inflation - Tire Pressure on page 5-70.
CAUTION: (Continued)
CAUTION: (Continued)

Overinated tires are more likely to be
cut, punctured, or broken by a sudden
impact — such as when you hit a
pothole. Keep tires at the
recommended pressure.
Worn, old tires can cause accidents.
If the tire’s tread is badly worn, or if
your vehicle’s tires have been
damaged, replace them.
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Tire Sidewall Labeling
Useful information about a tire is molded into its
sidewall. The examples below show a typical
passenger vehicle tire and a compact spare tire
sidewall.
(A) Tire Size
:The tire size is a combination of
letters and numbers used to dene a particular
tire’s width, height, aspect ratio, construction type,
and service description. See the “Tire Size”
illustration later in this section for more detail.(B) TPC Spec (Tire Performance Criteria
Specication)
:Original equipment tires designed
to GM’s specic tire performance criteria have
a TPC specication code molded onto the sidewall.
GM’s TPC specications meet or exceed all
federal safety guidelines.
(C) DOT (Department of Transportation)
:The
Department of Transportation (DOT) code
indicates that the tire is in compliance with the
U.S. Department of Transportation Motor Vehicle
Safety Standards.
(D) Tire Identication Number (TIN)
:The letters
and numbers following DOT (Department of
Transportation) code is the Tire Identication
Number (TIN). The TIN shows the manufacturer
and plant code, tire size, and date the tire was
manufactured. The TIN is molded onto both sides of
the tire, although only one side may have the date
of manufacture.
(E) Tire Ply Material
:The type of cord and
number of plies in the sidewall and under the tread.
(F) Uniform Tire Quality Grading (UTQG)
:Tire
manufacturers are required to grade tires based on
three performance factors: treadwear, traction, and
temperature resistance. For more information see
Uniform Tire Quality Grading on page 5-80. Passenger (P-Metric) Tire Example
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(G) Maximum Cold Ination Load
Limit:Maximum load that can be carried and the
maximum pressure needed to support that load.(A) Temporary Use Only:The compact spare tire
or temporary use tire has a tread life of
approximately 3,000 miles (5 000 km) and should
not be driven at speeds over 65 mph (105 km/h).
The compact spare tire is for emergency use when
a regular road tire has lost air and gone at.
If your vehicle has a compact spare tire, see
Compact Spare Tire on page 5-98andIf a Tire
Goes Flat on page 5-86.
(B) Tire Ply Material
:The type of cord and
number of plies in the sidewall and under
the tread.
(C) Tire Identication Number (TIN)
:The letters
and numbers following the DOT (Department of
Transportation) code is the Tire Identication
Number (TIN). The TIN shows the manufacturer
and plant code, tire size, and date the tire was
manufactured. The TIN is molded onto both sides of
the tire, although only one side may have the date
of manufacture.
Compact Spare Tire Example
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(D) Maximum Cold Ination Load
Limit:Maximum load that can be carried and the
maximum pressure needed to support that load.
(E) Tire Ination
:The temporary use tire or
compact spare tire should be inated to 60 psi
(420 kPa). For more information on tire pressure
and ination seeInflation - Tire Pressure on
page 5-70.
(F) Tire Size
:A combination of letters and
numbers dene a tire’s width, height, aspect ratio,
construction type, and service description. The
letter T as the rst character in the tire size means
the tire is for temporary use only.
(G) TPC Spec (Tire Performance Criteria
Specication)
:Original equipment tires designed
to GM’s specic tire performance criteria have
a TPC specication code molded onto the sidewall.
GM’s TPC specications meet or exceed all
federal safety guidelines.Tire Size
The following illustration shows an example of a
typical passenger vehicle tire size.
(A) Passenger (P-Metric) Tire
:The United States
version of a metric tire sizing system. The letter P
as the rst character in the tire size means a
passenger vehicle tire engineered to standards set
by the U.S. Tire and Rim Association.
(B) Tire Width
:The three-digit number indicates
the tire section width in millimeters from sidewall
to sidewall.
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(C) Aspect Ratio:A two-digit number that
indicates the tire height-to-width measurements.
For example, if the tire size aspect ratio is 60, as
shown in item C of the illustration, it would mean
that the tire’s sidewall is 60 percent as high as it
is wide.
(D) Construction Code
:A letter code is used to
indicate the type of ply construction in the tire.
The letter R means radial ply construction;
the letter D means diagonal or bias ply
construction; and the letter B means belted-bias
ply construction.
(E) Rim Diameter
:Diameter of the wheel in
inches.
(F) Service Description
:These characters
represent the load range and speed rating of the
tire. The load index represents the load carry
capacity a tire is certied to carry. The load index
can range from 1 to 279. The speed rating is the
maximum speed a tire is certied to carry a load.
Speed ratings range from A to Z.
Tire Terminology and Denitions
Air Pressure:The amount of air inside the
tire pressing outward on each square inch of the
tire. Air pressure is expressed in pounds per
square inch (psi) or kilopascal (kPa).
Accessory Weight
:This means the combined
weight of optional accessories. Some examples of
optional accessories are, automatic transmission,
power steering, power brakes, power windows,
power seats, and air conditioning.
Aspect Ratio
:The relationship of a tire’s height
to its width.
Belt
:A rubber coated layer of cords that is
located between the plies and the tread. Cords
may be made from steel or other reinforcing
materials.
Bead
:The tire bead contains steel wires wrapped
by steel cords that hold the tire onto the rim.
Bias Ply Tire
:A pneumatic tire in which the plies
are laid at alternate angles less than 90 degrees
to the centerline of the tread.
Cold Tire Pressure
:The amount of air pressure
in a tire, measured in pounds per square inch (psi)
or kilopascals (kPa) before a tire has built up heat
from driving. SeeInflation - Tire Pressure on
page 5-70.
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Curb Weight:The weight of a motor vehicle with
standard and optional equipment including the
maximum capacity of fuel, oil, and coolant, but
without passengers and cargo.
DOT Markings
:A code molded into the sidewall
of a tire signifying that the tire is in compliance
with the U.S. Department of Transportation (DOT)
motor vehicle safety standards. The DOT code
includes the Tire Identication Number (TIN), an
alphanumeric designator which can also identify the
tire manufacturer, production plant, brand, and date
of production.
GVWR
:Gross Vehicle Weight Rating. See
Loading Your Vehicle on page 4-21.
GAWR FRT
:Gross Axle Weight Rating for the
front axle. SeeLoading Your Vehicle on
page 4-21.
GAWR RR
:Gross Axle Weight Rating for the rear
axle. SeeLoading Your Vehicle on page 4-21.
Intended Outboard Sidewall
:The side of
an asymmetrical tire, that must always face
outward when mounted on a vehicle.
Kilopascal (kPa)
:The metric unit for air pressure.
Light Truck (LT-Metric) Tire
:A tire used on
light duty trucks and some multipurpose passenger
vehicles.Load Index
:An assigned number ranging from 1
to 279 that corresponds to the load carrying
capacity of a tire.
Maximum Ination Pressure
:The maximum air
pressure to which a cold tire can be inated. The
maximum air pressure is molded onto the sidewall.
Maximum Load Rating
:The load rating for a tire
at the maximum permissible ination pressure
for that tire.
Maximum Loaded Vehicle Weight
:The sum of
curb weight, accessory weight, vehicle capacity
weight, and production options weight.
Normal Occupant Weight
:The number of
occupants a vehicle is designed to seat multiplied
by 150 lbs (68 kg). SeeLoading Your Vehicle
on page 4-21.
Occupant Distribution
:Designated seating
positions.
Outward Facing Sidewall
:The side of an
asymmetrical tire that has a particular side that
faces outward when mounted on a vehicle. The
side of the tire that contains a whitewall, bears
white lettering, or bears manufacturer, brand,
and/or model name molding that is higher or deeper
than the same moldings on the other sidewall of
the tire.
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Passenger (P-Metric) Tire:A tire used on
passenger cars and some light duty trucks and
multipurpose vehicles.
Recommended Ination Pressure
:Vehicle
manufacturer’s recommended tire ination
pressure as shown on the tire placard. See
Inflation - Tire Pressure on page 5-70andLoading
Your Vehicle on page 4-21.
Radial Ply Tire
:A pneumatic tire in which the ply
cords that extend to the beads are laid at
90 degrees to the centerline of the tread.
Rim
:A metal support for a tire and upon which
the tire beads are seated.
Sidewall
:The portion of a tire between the tread
and the bead.
Speed Rating
:An alphanumeric code assigned to
a tire indicating the maximum speed at which a
tire can operate.
Traction
:The friction between the tire and the
road surface. The amount of grip provided.
Tread
:The portion of a tire that comes into
contact with the road.Treadwear Indicators
:Narrow bands, sometimes
called wear bars, that show across the tread of
a tire when only 1/16 inch (1.6 mm) of tread
remains. SeeWhen It Is Time for New Tires on
page 5-77.
UTQGS (Uniform Tire Quality Grading
Standards)
:A tire information system that
provides consumers with ratings for a tire’s
traction, temperature, and treadwear. Ratings are
determined by tire manufacturers using
government testing procedures. The ratings are
molded into the sidewall of the tire. SeeUniform
Tire Quality Grading on page 5-80.
Vehicle Capacity Weight
:The number of
designated seating positions multiplied by 150 lbs
(68 kg) plus the rated cargo load. SeeLoading
Your Vehicle on page 4-21.
Vehicle Maximum Load on the Tire
:Load on an
individual tire due to curb weight, accessory
weight, occupant weight, and cargo weight.
Vehicle Placard
:A label permanently attached to
a vehicle showing the vehicle’s capacity weight
and the original equipment tire size and
recommended ination pressure. See “Tire and
Loading Information Label” underLoading
Your Vehicle on page 4-21.
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Ination - Tire Pressure
Tires need the correct amount of air pressure to
operate effectively.
Notice:Do not let anyone tell you that
under-ination or over-ination is all right. It is
not. If your tires do not have enough air
(under-ination), you can get the following:
Too much exing
Too much heat
Tire overloading
Premature or irregular wear
Poor handling
Reduced fuel economy
If your tires have too much air (over-ination),
you can get the following:
Unusual wear
Poor handling
Rough ride
Needless damage from road hazardsA vehicle specic Tire and Loading Information
label is attached to your vehicle. This label shows
your vehicle’s original equipment tires and the
correct ination pressures for your tires when they
are cold. The recommended cold tire ination
pressure, shown on the label, is the minimum
amount of air pressure needed to support your
vehicle’s maximum load carrying capacity.
For additional information regarding how much
weight your vehicle can carry, and an example of
the Tire and Loading Information label, see
Loading Your Vehicle on page 4-21. How you load
your vehicle affects vehicle handling and ride
comfort. Never load your vehicle with more weight
than it was designed to carry.
When to Check
Check your tires once a month or more. Do not
forget to check the compact spare tire, it should be
at 60 psi (420 kPa). For additional information
regarding the compact spare tire, seeCompact
Spare Tire on page 5-98.
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Please note that the TPMS is not a substitute for proper
tire maintenance, and it is the driver’s responsibility to
maintain correct tire pressure, even if under-ination has
not reached the level to trigger illumination of the TPMS
low tire pressure telltale.
Your vehicle has also been equipped with a TPMS
malfunction indicator to indicate when the system is not
operating properly. The TPMS malfunction indicator
is combined with the low tire pressure telltale. When the
system detects a malfunction, the telltale will ash for
approximately one minute and then remain continuously
illuminated. This sequence will continue upon
subsequent vehicle start-ups as long as the malfunction
exists.
When the malfunction indicator is illuminated, the
system may not be able to detect or signal low tire
pressure as intended. TPMS malfunctions may occur for
a variety of reasons, including the installation of
replacement or alternate tires or wheels on the vehicle
that prevent the TPMS from functioning properly. Always
check the TPMS malfunction telltale after replacing one
or more tires or wheels on your vehicle to ensure that the
replacement or alternate tires and wheels allow the
TPMS to continue to function properly.
SeeTire Pressure Monitor Operation on page 5-73, for
additional information.Federal Communications Commission
(FCC) and Industry and Science
Canada
The Tire Pressure Monitor System (TPMS) operates on
a radio frequency and complies with Part 15 of the
FCC Rules. Operation is subject to the following
two conditions:
1. This device may not cause harmful interference.
2. This device must accept any interference received,
including interference that may cause undesired
operation.
The Tire Pressure Monitor System (TPMS) operates on
a radio frequency and complies with RSS-210 of
Industry and Science Canada. Operation is subject to
the following two conditions:
1. This device may not cause interference.
2. This device must accept any interference received,
including interference that may cause undesired
operation of the device.
Changes or modications to this system by other than
an authorized service facility could void authorization to
use this equipment.
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Tire Pressure Monitor Operation
The Tire Pressure Monitor System (TPMS) is designed
to warn the driver when a low tire pressure condition
exists. TPMS sensors are mounted onto each tire and
wheel assembly, excluding the spare tire and wheel
assembly. The TPMS sensors monitor the air pressure in
the vehicle’s tires and transmits the tire pressure readings
to a receiver located in the vehicle.
When a low tire pressure
condition is detected, the
TPMS illuminates the low
tire pressure warning light
located on the instrument
panel cluster.
If your vehicle has the uplevel Driver Information Center
(DIC), a warning message to check the pressure in a
specic tire displays at the same time the low tire
pressure warning light comes on. The low tire pressure
warning light and the DIC warning message come on at
each ignition cycle until the tires are inated to the correctination pressure. Vehicles that have the uplevel DIC
buttons can also check tire pressure levels by pressing
the gages button. For additional information and details
about the DIC operation and displays seeDIC Operation
and Displays on page 3-50andDIC Warnings and
Messages on page 3-58
The low tire pressure warning light may come on in cool
weather when the vehicle is rst started, and then turn
off as you start to drive. This could be an early indicator
that the air pressure in the tire(s) are getting low and
need to be inated to the proper pressure.
A Tire and Loading Information label, attached to your
vehicle, shows the size of your vehicle’s original
equipment tires and the correct ination pressure for
your vehicle’s tires when they are cold. SeeLoading
Your Vehicle on page 4-21, for an example of the Tire
and Loading Information label and its location on your
vehicle. Also seeInflation - Tire Pressure on page 5-70.
Your vehicle’s TPMS system can warn you about a low
tire pressure condition but it does not replace normal
tire maintenance. SeeTire Inspection and Rotation on
page 5-75andTires on page 5-63.
Notice:Liquid tire sealants could damage the Tire
Pressure Monitor System (TPMS) sensors. Sensor
damage caused by using a tire sealant is not
covered by your warranty. Do not use liquid tire
sealants.
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